František Včelař and  Zuzana Pátíková,  On Tarski’s Type Theorems for L-Fuzzy Isotone and L-Fuzzy Relatively Isotone Maps on L-Complete Propelattices.   journal   = {International Journal of Mathematical and Computational Sciences}, [online]. World Academy of Science, Engineering and Technology.
    June 2016, vol. 111(3). 143 - 150
    [viewed 11 May 2024]. Available from: https://publications.waset.org/pdf/10005160.